Summations Problem: Sum of Multiples of 5 from 5-1550

[elainehula]

Homework Statement

Sum all the whole numbers which are multiples of 5 from 5 to 1550

Homework Equations

The Attempt at a Solution

1550÷5=310
1550-5x310= 478950

 

[LCKurtz]

Homework Statement

Sum all the whole numbers which are multiples of 5 from 5 to 1550

Homework Equations

The Attempt at a Solution

1550÷5=310
1550-5x310= 478950

Hint: Sum of arithmetic progression or, alternatively,$$
\sum_{k=1}^{310}5k = 5\sum_{k=1}^{310}k$$

 

[HallsofIvy]

Homework Statement

Sum all the whole numbers which are multiples of 5 from 5 to 1550

Homework Equations

The Attempt at a Solution

1550÷5=310

Yes, that is correct

1550-5x310= 478950

No, 1550- 5x 310= 0, That is what $$1550÷5= 310$$ means!

 

[Bacle2]

Yes, that is correct


No, 1550- 5x 310= 0, That is what $$1550÷5= 310$$ means!

She is using the parentheses differently (incorrectly so , by priority of operations):

1550-5=1545 , 1545x310= 474950